.\" Copyright (c) 2020 Vladimir Kondratyev <wulf@FreeBSD.org>
.\"
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.Dd September 21, 2020
.Dt IICHID 4
.Os
.Sh NAME
.Nm iichid
.Nd I2C HID transport driver
.Sh SYNOPSIS
To compile this driver into the kernel,
place the following lines in your
kernel configuration file:
.Bd -ragged -offset indent
.Cd "device iichid"
.Ed
.Pp
Alternatively, to load the driver as a
module at boot time, place the following line in
.Xr loader.conf 5 :
.Bd -literal -offset indent
iichid_load="YES"
.Ed
.Sh DESCRIPTION
The
.Nm
driver provides a interface to I2C Human Interface Devices (HIDs).
.Sh SYSCTL VARIABLES
Next parameters are available as
.Xr sysctl 8
variables.
Debug parameter is available as
.Xr loader 8
tunable as well.
.Bl -tag -width indent
.It Va dev.iichid.*.sampling_rate_fast
Active sampling rate in num/second (for sampling mode).
.It Va dev.iichid.*.sampling_rate_slow
Idle sampling rate in num/second (for sampling mode).
.It Va dev.iichid.*.sampling_hysteresis
Number of missing samples before enabling of slow mode (for sampling mode).
.It Va hw.iichid.debug
Debug output level, where 0 is debugging disabled and larger values increase
debug message verbosity.
Default is 0.
.El
.Sh SEE ALSO
.Xr ig4 4
.Sh BUGS
The
.Nm
does not support GPIO interrupts yet.
In that case
.Nm
enables sampling mode with periodic polling of hardware by driver means.
See dev.iichid.*.sampling_*
.Xr sysctl 8
variables for tuning of sampling parameters.
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 13.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Marc Priggemeyer Aq Mt marc.priggemeyer@gmail.com
and
.An Vladimir Kondratyev Aq Mt wulf@FreeBSD.org .
.Pp
This manual page was written by
.An Vladimir Kondratyev Aq Mt wulf@FreeBSD.org .
